Chap 1 - Network Fundamentals - Part 2 Flashcards
1-159: To which class does the following IPv4 address belong: 190.126.14.251
Class A
Class B
Class C
Class D
Class B
Class A: 1 to 126 - Many hosts per network.
Class B: 128 to 191 - Many hosts per network.
Class C: 192 to 223 - Many networks with fewer hosts per network.
Class D: 224 to 239 - Multicasting.
Class A octet range
1 to 126
Class B octet range
128 to 191
Class C octet range
192.0.0.0 to 223.255.255.255
Class D octet range
224 to 239
CIDR
- Classless Inter-Domain Routing (CIDR)
- method used to create smaller network segments or subnets from a single block of IP addresses
- essential for efficient use of IP address space and network management.
CIDR allows for more flexible allocation of IP addresses compared to the traditional class-based system by using variable-length subnet masking, which enables the division of an IP address space into subnets of different sizes.
VLSM
Variable Length Subnet Masking
echnique that allows the subdivision of an IP network into smaller, variably sized subnets, providing more efficient use of IP addresses.
Unlike traditional fixed-length subnetting, which divides an IP address space into subnets of equal size, VLSM enables the creation of subnets with different sizes, tailored to the specific number of hosts required in each subnet.
EUI-64
technique to create IPv6 link local address from MAC address
1-161: Ralph has been instructed to use the network address of 10.12.0.0/14 for the new network he is installing. What subnet mask value should he use when configuring his computers?
255.248.0.0
255.252.0.0
255.254.0.0
255.255.248.0
255.255.252.0
255.255.254.0
How to get this?
- /14 = 14 bits for network
- so this is 18 bits for host, or 32 bits total
- converted to binary and displayed as an IP address:
11111111.11111100.00000000.00000000 - or converted to decimal: 255.252.0.0
1-162: Ed has been hired to design a company’s network. The company has an assigned Class C network address of 192.168.30.0. Ed’s client wants the network to be configured with 10 subnets, each with 14 hosts. Is this configuration possible with the given address, and if so, how many subnets and hosts can Ed create on the network?
Yes, this will work. By using 4 subnet bits, it is possible for Ed to create up to 16 subnets. He can then use the remaining 4 host bits to create 14 hosts on each subnet
No, this will not work. A Class C address cannot be subnetted to create 8 subnets
No, this will not work. Although there are sufficient bits available to create 10 subnets, there are not enough bits left over for Ed to create 14 hosts per subnet
Yes, this will work. Ed can create 10 subnet bits with 14 hosts per subnet. By using 3 subnet bits, he can create 10 subnets, which leave 5 bits to create up to 30 hosts per subnet
How to get this?
1. Class C has 24 network bits and 8 host bits, remember Class C is 255.255.255.0, or 11111111.11111111.11111111.00000000
2. Ed must subdivide the 8 host bits into subnet and hosts
3. 14 hosts + 2 extra (network and Broadcast) = 16. 2^4 = 16, so 4 host bits, leaves 4 bits for network, or a maximum of 16 subnets
Yes, this will work. By using 4 subnet bits, it is possible for Ed to create up to 16 subnets. He can then use the remaining 4 host bits to create 14 hosts on each subnet
1-163: What is the greatest number of subnets you can create with a Class A IPv4 address if you use a 14-bit subnet identifier?
256
1022
1024
16382
16384
16384
2^14 = 16384
1-164: Alice has been asked to design her company’s IPv4 addressing scheme. The company has been assigned a Class C network address of 192.168.30.0. Alice’s director wants 4 subnets with 28 hosts per subnet. How many bits are required for the subnets? How many bits are required for hosts? What will the new subnet mask be for the network?
3 subnet bits, 5 host bits, subnet mask: 255.255.255.240
4 subnet bits, 3 host bits, subnet mask: 255.255.255.248
3 subnet bits, 5 host bits, subnet mask: 255.255.255.224
53 subnet bits, 3 host bits, subnet mask: 255.255.255.192
how to get it?
1. 28 hosts + 2 (network and broadcast)
2. 2^5 = 32, which is enough for 30 hosts
3. 5 bits for hosts, 3 bits for subnet, 8 bits total available on a Class C network
4. 11100000, or 224
5. answer is: 3 subnet bits, 5 host bits, subnet mask: 255.255.255.224
1-165: A network interface adapter in a workstation has a hex MAC address of 001F9EFC7AD0. Which of the following would be the adapter’s IPv6 link local address based on its EUI-64 value?
FE80::001F:9EFF:FEFC:7AD0
FE80::FFFE:021F:9EFC:7AD0
FE80::FF00:1F9E:FC7A:D0FE
FE80::021F:9EFF:FEFC:7AD0
How to do this?
1. MAC address is 6-bytes, split into 2, 3-byte addresses, in this case:
001F9E FC7AD0
2. add the value FFFE in between to get:
001F9E FFFE FC7AD0
3. 7th bit in first byte has to change from 0 to 1 to indicate this is local created
so you get 00000010, which is 02 in hex
4. add FE80::/10 to get: FE80::021F:9EFF:FEFC:7AD0
1-166: The default mask for a IPv4 Class B network is 255.255.0.0. How many subnet bits do you need to create 600 subnets with 55 hosts per subnet, and what is the new subnet mask?
10 subnet bits with a subnet mask of 255.255.255.192
9 subnet bits with a subnet mask of 255.255.255.128
10 subnet bits with a subnet mask of 255.255.224.0
11 subnet bits with a subnet mask of 255.255.255.192
How to get this?
1. 55 hosts is 55 + 2 (network and Broadcast)
2. 57 hosts, fits in 2^6= 64, or 6 bits for host
3. so 10 bits for subnet, becayse Class B is 16 bits total
4. 11111111.11000000 is the subnet and host bits in binary
5. convert to decimal: 255.192 or
10 subnet bits with a subnet mask of 255.255.255.192
1-167: What is the greatest number of host addresses you can create on a single subnet of the network with the following address: 172.16.0.0/20?
142
144
4094
4096
How to get it?
1. /20 network has 20 bits for network, and 12 left for host, as its 32 bits total
2. 2^12 = 4096, 12 for hosts. However you need to subtract 2, for the network and broadcast
3. 4096 - 2 = 4094
1-168: Ralph has a IPv4 Class B netywork with a subnet mask of 255.255.248.0. How many subnets can he create and how many hosts can he create per subnet?
64 subnets and 2046 hosts
32 subnets and 2046 hosts
30 subnets and 1022 hosts
62 subnets and 1022 hosts
how to get this?
1. convert Class B subnet into binary, only need to worry about ending 16-bits cause its class B, so 248.0 comes ot: 11111000.00000000
2. this gives us 5 bits for subnet, 11 bits for host
3. 2^5 = 32
4. 2^11 = 2048 - 2 for network and broadcast
5. so the answer is:
32 subnets and 2046 hosts
1-170: If you have an IPv4 address of 192.168.1.32/27, what is the valid range of host addresses you can use for your workstations?
192.16.1.33 thru 192.168.1.63
192.16.1.33 thru 192.168.1.62
192.16.1.34 thru 192.168.1.62
192.16.1.34 thru 192.168.1.63
How to get this?
1. /27 network means 27 bits for subnet and 5 for hosts (32-27 = 5)
2. valid range of host bits is then 00001 (1) thru 11110 (30)
3. range starts as one on top of address, so 192.168.1.32 + 1 = 192.168.1.33
4. range finishs as 30 after the address, so 192.168.1.32 + 30 = 192.168.1.62
5. so:
192.16.1.33 thru 192.168.1.62
1-171: Alice has been assigned the IPv4 network address of 172.21.0.0/22 for the creation of a new department network in her company. How many host addresses does she have available to her?
510
512
1022
1024
How to get this?
1. /22 means 22 subnet or network bits
2. so 10 host bits
3. the formula is 2^host bits - 2 (for network and broadcast addresses)
4. so 2^10 = 1024 - 2
1022
What IPv4 network class is used for multicast?
Class D
1-174: Which of the following is an address that you can assign to a host on a private IPv4 network?
192.167.9.46
172.16.255.255
10.1.0.253
225.87.34.1
10.1.0.253
Why?
* 192.167.9.46 - valid range is 192.168.0.0 - 192.168.255.255
* 172.16.255.255 - wildcard.255.255 is a brodcast address
* 225.87.34.1 - obviously outside of private range
1-177: Which of the following IPv4 addresses is available for use on a network device?
1.0.0.1
127.98.127.0
234.9.76.32
240.65.8.124
1.0.0.1
1-178: Which of the following IPv6 address types is the functional equivalent of an IPv4 APIPA address?
Link local
Global Unicast
Site local
Anycast
Link local
127.0.0.1 in IPv6 and name
127.0.0.1 is called the loopback address in both IPv4 andIPv6
in IPv6 its ::1
1-179: When two workstations access the internet using the same Port Address Translation (PAT) router, which of the following does the router assign to each workstation? (Choose all that apply)
A unique port number
A common public IPv4 address
A common port number
A unique public IPv4 address
A unique port number
A common public IPv4 address
PAT
- Port Address Translation (PAT)
- specific type of Network Address Translation (NAT)
- allows multiple devices on a local network to be mapped to a single public IP address but with a different port number for each session
- most common form of NAT used to handle the “one-to-many” connection, enabling numerous internal hosts to share a single external IP address.
Two workstations accessing the internet via the same PAT router have:
* A unique port number
* A common public IPv4 address
1-180: Which of the following is the IPv6 equvialent of APIPA?
EUI-64
SLAAC
DHCPv6
APIPAv6
SLAAC
SLAAC
Stateless Address Autoconfiguration
means by which IPv6 systems self-generate link local addresses with the prefix - fe80::/64
What are the ports for:
- FTP
- TFTP (trivial FTP)
- SSH
- Telnet
- SMTP
- DNS
- DHCP
- HTTP
- POP3
- NetBios/NetBT
- IMAP
- SNMP
- LDAP
- HTTPS
- SMB/CIFS
- RDP
- FTP - 20/21
- SSH - 22
- Telnet - 23
- SMTP - 25
- DNS - 53
- DHCP - 67/68
- TFTP - 69
- HTTP - 80 (also sometimes 8080)
- POP3 - 110
- NetBios/NetBT - 137/139
- IMAP - 143
- SNMP - 161/162 (UDP)
- LDAP - 389
- HTTPS - 443
- SMB/CIFS - 445 (Common Internet File System, CIFS, is a dialect of SMB)
- RDP - 3389
1-181: Which of the following are mechanims by which IPv6 traffic can be transmitted on an IPv4 network thru the use of tunneling? (Choose all that apply)
Teredo
IPsec
ICMPv6
6to4
Teredo
6to4
Teredo
Teredo is a tunneling protocol designed to grant IPv6 connectivity to nodes that are on IPv4 Internet but without any native connection to an IPv6 network. Teredo works by encapsulating IPv6 packets within IPv4 User Datagram Protocol (UDP) packets.
6to4
6to4 is an IPv6 tunneling protocol that allows for the transmission of IPv6 packets over an IPv4 network without the need for a tunnel broker. It is typically used to connect two routers directly and generally requires a public IPv4 address to function
1-182: Which of the following best describes why IPv6 hosts exchange ICMPv6 Router Solicitation and Router Advertisement messages with routers?
To obtain the prefix needed to generate a link-local address
To learn the IPv6 address of the nearest router
To perform address conflict detection for its link-local address
To encapsulate IPv4 pakcets and transmit them over the router
To obtain the prefix needed to generate a link-local address
1-183: Which of the following are examples of Virtual IP (VIP) addresses? (Choose all that apply)
An IP address assigned to a host workstation by a DHCP server
A public IP address subsituted for a host’s own private IP address by a NAT router
An IP address assigned to a host workstation by APIPA
An IP address assigned to a virtual NIC
A public IP address subsituted for a host’s own private IP address by a NAT router
An IP address assigned to a virtual NIC
1-184: Which of the following is the best description of a subinterface?
- A logical network interface created from a physical network interface
- One of the ports on a physical network interface adapter with multiple ports
- A physical network interface conected to a subnet
- One of the IP addresses associated with a network interface that has multiple IP addresses
A logical network interface created from a physical network interface
1-186: Which of the following server applications uses two well-known port numbers during a typical transaction?
NTP
SNMP
HTTP
FTP
FTP uses port 21 to establish a connection and port 20 to send data
also, bullshit question as SNMP uses 161/162, though 162 is UDP and only used for SNMP traps, aka where an agent (the device being managed) can alert the SNMP manager (the system managing the device) to a significant event or change in status.
1-188: Which of the following components does the port number in transport layer protocol header identify?
A transport layer protocol
An application
A gateway
A proxy server
An application
1-189: Which of the following organizations is responsible for assiging the well-known port numbers used in transport layer protocol headers?
IEEE
IANA
IETF
ISO
IANA
IEEE
Institute for Electronic and Eletrical Engineers
publishes ethernet standards, among other things
IANA
Internet Assigned Numbers Authority
Assigns values for well known port numbers
IETF
Internet Engineering Task Force
develops standards for internet technologies
ISO
International Standards Organization
developed the OSI model
MSS
Maximum Segment Size
field in TCP option subheader to specify the size of the largest segment a system can control
Socket
combination of IPv4 address and port, such as:
192.168.1.47:25
OUI
Organizationally Unique Identifier
identifies the manufacturer of network hardware
1-194: Which of the following protocols generate messgaes that are carried directly within IPv4 datagrams, with no intervening transport layer protocol? (Choose all that apply)
ICMP
IGMP
SMTP
SNMP
ICMP
IGMP
datagram
- connectionless transfer unit used within the UDP (User Datagram Protocol) framework
- designed for quick transfers over a packet-switched network.
This approach allows for the transmission of packets without establishing a dedicated end-to-end connection, making the process efficient for scenarios where speed and simplicity are more critical than reliability and order.
Advanced Ports to Know
- SMTP over TLS
- POP3 over TLS
- IMAPS (IMAP over SSL)
- SQL ports
- Unix Logging Systems aka syslog
- LDAP over SSL
- SMTP over TLS: 587
- POP3 over TLS: 995
- IMAPS: 993
- SQL: 1433 (SQL Server), 1521 (SQLnet), 3306 (MySQL)
- syslog: 514
- LDAP over SSL: 636
1-201: Which of the following protocols use(s) the term datagram to describe the data transfer unit it creates? (Choose all that apply)
Ethernet
IP
TCP
UDP
IP
UDP
What term does TCP use to describe the data transfer unit it creates?
segment
What term does Ethernet use to describe the data transfer unit it creates?
frame
Ephemereal client ports range
49152 - 65535
Well known TCP and UDP ports range
1 -1023
Registered port numbers range
1024-49151
1-208: Which of the following statements about UDP are true? (Choose all that apply)
UDP does not use packet sequencing and acknowledgements
UDP uses packet sequencing and acknowledgements
UDP is a connection orientated protocol
UDP is a connection-less protocol
UDP has an 8-byte header
UDP has an 20-byte header
UDP does not use packet sequencing and acknowledgements
UDP is a connection-less protocol
UDP has an 8-byte header